The present invention relates to a roof ridge ventilator, and more particularly, to a roof ridge ventilator which ventilates air from beneath a roof, while also causing outside air to assist in removing air from beneath the roof, without interfering with upwardly facing vent openings.
The need for attic ventilation is well established and is two-fold in nature: reduction of summer heat build-up and preventing winter moisture condensation.
In summer, the principal source of attic heat is direct sunlight (radiated heat) on the roof of a home. Unless ventilated, intense attic heat is transmitted to and through the ceiling surfaces of the living space below. Not only do rooms become hotter, this further adds to the air conditioning requirement, both in the size of the unit needed and in operating costs. While ceiling insulation retards the rate at which heat flows to the rooms below, ventilating heat from the attic makes the insulation more effective and reduces the quantity of heat stored in the insulation. Ventilation also provides quicker and more complete cooling of the attic during the night, while also minimizing or limiting seasonal build-up of heat.
In winter, ventilating the attic space is equally important. The trend toward the use of insulation, in order to reduce heat flow from the attic to living quarters during the summer and heat loss in the winter, has been accompanied by tighter new home construction. Specifically, tighter new home construction is designed to prevent outside air from entering the home, while preventing the escape of interior air. While tighter new home construction coupled with greater use of insulation does in fact seal the home from outside air while preventing the escape of interior air, little consideration has been given to the release of water vapor into the home. The use of automatic laundry equipment, more frequent use of bath and shower facilities and the addition of humidifiers to heating equipment has created greater water vapor in the home. As a result, enough water vapor can escape to the attic to condense on cold inner roof surfaces, and in some cases, the amount of water vapor has been sufficient to saturate the rafters and roof sheathing, causing serious deterioration. The need for winter time attic ventilation, in addition to summer attic ventilation, has therefore, become readily apparent.
There are a number of different types of attic ventilators including roof louvers (with or without a turbine wheel activated by the wind to draw air out of the attic), gabled end louvers, soffit vents, roof ridge vents, or a combination of one or more of the above. While there are advantages and disadvantages to each of the foregoing types of roof ventilating systems, the present invention is directed to a roof ridge ventilator which, as will be made more apparent from the discussion that follows, enjoys more advantages, without the disadvantages of the other attic ventilation systems, as will become apparent.
Prior art roof ridge ventilator may be categorized generally into two different: those which are made of metal such as aluminum or zinc, and those which are molded from one or more plastic parts. The metal roof ridge ventilators, formed in one or more metal parts, typically include a top or roof cover for overhanging the open roof ridge with a series of louvered vent openings provided in undersurfaces of the top or cover. Wind deflectors or baffles associated with water weep openings are provided on opposite sides of such roof ridge ventilators generally adjacent an elongated ridge or groove, with the baffles serving to direct wind across the top or cover of the roof ridge ventilator while the vents openings on the undersurface of the top or cover enable air to be vented from beneath the roof. Some prior art examples of such metal roof ridge ventilators are shown in U.S. Pat. Nos. 3,079,853; 3,303,773; 4,554,862 and 4,643,080.
Other examples of wind deflector or baffle features in metal roof ridge ventilators are shown in U.S. Pat. Nos. 4,090,435; 4,325,290; 4,621,569 and 4,642,958. In some cases, the wind deflector or baffle structure is associated with louvers or vents to allow outside air to be directed away from the vents through which the inside air is ventilated.
Roof ridge ventilators which are molded as a single unit or in a plurality of parts are shown in U.S. Pat. Nos. 3,949,657; 4,280,399; 4,676,147; 4,817,506 and RE 27,943. In each of these aforementioned patents, one or more molded plastic parts form a roof ridge ventilator allowing air to be readily exhausted through vent openings provided in the roof ridge ventilator, while at the same time preventing outside air from being directed into the roof ridge ventilator.
Although the above and other prior art designs have worked well for the purposes intended, there are numerous disadvantages. In addition to the prior art designs requiring multiple part constructions, they do not effectively cause outside air to move past vent openings, but instead allow air to blow in the vent openings. At the same time, the prior art designs do not allow efficient cubic feet of air movement per foot of ventilation, as is required in construction standards and specifications. In addition, prior art designs do not prevent snow, rain or any other kind of moisture from getting inside the roof ridge ventilator, and thus may cause deterioration problems beneath the roof.